Work out help!!!!

I have a friend that had a baby about 2 months ago and she has been working out for at least 30 minutes everyday and is not seeing any results, her skin is making her so self conscious because of the flap and flop. Any help would be great! She said she has been doing squats sit-ups plank, but it's not doing anything... She is a beautiful person and does not need to feel so self conscious so please help me help her....